Peacock flounders change color to camouflage with their surroundings to reduce the chances of being noticed by their predators.
The peacock flounder (Bothus mancus), also known as the flowery flounder, is a species of fish in the family Bothidae. The species is found widely in relatively shallow waters in the Indo-Pacific, also ranging into warmer parts of the East Pacific.
Like all flounders, peacock flounders are masters of camouflage. They use cryptic coloration to avoid being detected by both prey and predators. Whenever possible rather than swim they crawl on their fins along the bottom while constantly changing colors and patterns. In a study, peacock flounders demonstrated the ability to change colors in just eight seconds.
They were even able to match the pattern of a checkerboard they were placed on. The changing of the colors is an extremely complex and not well-understood process. It involves the flounder's vision and hormones. The flounders match the colors of the surface by releasing different pigments to the surface of the skin cells while leaving some of the cells white by sequestering those pigments.
If one of the flounder's eyes is damaged or covered by sand, the flounders have difficulties in matching their colors to their surroundings. When hunting or hiding from predators, the flounders bury themselves in the sand, leaving only the eyes protruding.